The objective of this project is to elucidate some of the factors which regulate and control the translational process in normal and virus infected bacterial cells. We have pursued this problem by studying some of the biochemical properties of T4 and T5 bacteriophage specific transfer RNAs (coded for by the bacteriophage genome) and by examining functional changes in E. coli ribosomes following phage infection. Some of our current projects concerning T5 tRNA synthesis include (a) at what time after infection t5 tRNAs are made; (b) which portion of the phage genome codes for T5 tRNA; (c) which of the two DNA strands carries this information; and (d) whether we can physically isolate T5 DNA pieces enriched in their content for tRNA. We hope to synthesize T5 tRNA precursors, in vitro, so that we may study the tRNA maturation process. We are also attempting to analyze ribosomes, from normal and infected cells, for their content of individual proteins by two dimensional gel electrophoresis. The problem of ribosomal heterogeniety with respect to function still remains unresolved.